Heidi and Halle Foxcroft

Miss Foxcroft underwent an operation to remove her last remaining fallopian tube in January 2013 following a third ectopic pregnancy, which ended all her hopes of having another child.

Ten days after the operation, a stunned Miss Foxcroft was told she was not only still pregnant – but was expecting twins.

Doctors told Miss Foxcroft and partner Ross Whitehead, 30, that the twins were growing in the same amniotic sac and had little chance of survival.

The twins, who both had underdeveloped lungs when they were born five-weeks prematurely in August 2013, were cared for on the neonatal intensive care unit at St James’s Hospital in Leeds.

Miss Foxcroft, who also has a four-year-old son, Harry, said: “When we found out I was still pregnant and the babies had survived it was a real miracle.

“Over the past two years the most frequently asked question we have had is ‘bet they are hard work’ or the ‘double trouble’ quote. The answer is yes, the last two years have been hard work.

“But we are eternally grateful to have both our girls. After everything we went through as a family to bring them into the world we feel extremely lucky.

“Even though they are double trouble we are blessed with double the cuddles and double the joy. This Sunday is their second birthday and I’d like to take this opportunity to again thank St James’s staff and neonatal care for caring for our girls through what was a very emotional and difficult pregnancy and bringing our girls safely into the world and caring for them afterwards.”

Miss Foxcroft and her friend and the twins’ godmother Sophie Bashforth, 27, ran the Leeds Half Marathon in May and raised almost £1,000 for St James’s Hospital.